Envelope flap folding machine



Mam}! 1944- D. E. STEVENSON ENVELOPE FLAP FOLDING MACHINE 3 Sheets-Shae 1 Filed Feb. 21, 1941 (7770/F/VE r.

March 14, 19 44. D STEVENSON 2,344,220

ENVELOPE FLAP FOLD ING MACHINE Filed Feb. 21, 1941 5 Sheets-Sheet 2 Fig.5.. 40

INVENTOR:

March 14, 1944.

ENVELOPE FLAP FOLDING MACHINE Filed Feb. 21, 1941 3 Sheets-Sheet 3 IN VEN 7' OR.

BY 62 Q D. E. STEVENSON I 2,344,220 2 Patented Mar. 14, 1944 Donald E. Stevenson,

Carpenter Paper Company,

Monrovia, Calif., assignor to a corporation of Application February 21, 1941, Serial No. 379,922

18 Claims.

The present inventionhas relation to the type of envelope folding machines into which correctly formed blanks are fed, and in which the various folds successively are completed and the bottom and end fiaps glued in position. The top flap is, in most cases, folded over the three other flaps, but it is sometimes not folded at all.

Lately, however, it has-become quite common to fold the top flap back. over the front of the envelope, particularly .in' case of return envelopes on which the return address haspreviously been printed. On the exposed inner surface of the fiap is printed notices, which it is the desire of the sender to present to the recipient before the latter uses the envelope for return mailing. It-has been customary too, in making this type of envelope, town the form through the machine without folding the top flap, and later manually to make the reverse fold, an operation which nearly doubles the cost of this type of envelope. 1

In view of the foregoing, it is the object of the present invention to provide a simple and efficient device for folding the top fiap ofan envelope over the face thereof .It is a further object to provide a folding device of this type which may readily be embodied in commercially known folding machines to the end that this reverse fold may be made at no additional cost.

Drawings are hereto annexed in which preferred forms of the invention are illustrated, and a detailed description follows, fully explaining the operation of the device illustrated in the drawings in order to enable those versed in the art to construct. a machine in accordance with the invention.

In the drawings:

Fig. 1 is a side elevational view of a device embodying the invention',-the front portion of the framing being broken away in order to facilitate reading of the drawing; a

Fig. 2 is a substantially corresponding plan view of the device, showing the important parts thereof; 7

Figs. 3 and 4 are fragmentary views, substantially in agreement with Fig. 1 and illustrating the device in different positions of adjustment; and I'.

Figs. 5 and 6 arefragmentary views of certain parts of the device in winch-modifications are embodied, the importance of which will .hereinafter fully be explained.

The device of the invention is,'1n' Figs. 1 and 2, shown to comprise a frame 'I having a flat top plate 2, along which an envelope may be ,arm 2| of a second rockshaft 22, and

fed to a scoring roller 3 having a transverse ridge 4 for indenting the envelope at the point where it is desired to turn the flap back over the front of the envelope. As best shown in Fig. 2, the bottom edge of the envelope first passes underthe scoring roller. At the end of the top plate, directly ahead of the scoring roller, are placed feed rollers 5 and 6, which are shown positioned to pick up the envelope as it leaves the scoring roller and to carry it forward to the fiap folding mechanism.

The first and most important element of this folding mechanism to be encountered by the bottom edge of the envelope is a plate, or shovel 1, which for convenience may be termed a carrier the upper edge of which is journaled on a rod 8, forming part of a transverse rock frame 9. It is noticed that the upper portion of this shovel is substantially flat and that the lower portion thereof curves rearwardly until it reaches the roller 6; see Fig. l.

Before entering upon a detailed description of the various features of the folding mechanism, it may facilitate perusal thereof briefly to outline the functioning of this shovel. As the envelope continues its forward movement, its bottom edge is caused to ride along this curved portion of the shovel until arrested by suitable stops l0 thereof, whereupon the shovel is caused to swing forward into the position indicated in Fig. 3, entirely to withdraw the envelope from the feed rollers 5 and 6. When thereupon the shovel again is swung back, it is found that the flap is folded back on the scored indentation and that the top edge of the finished envelope is guided between the roller 6 and a return roller H, finally to be deposited on a delivery table I2. This completes one cycle of operation.

Returning now to Fig. 1, it is noticed that the rock frame 9, through the medium of a pivotally hung link 29, is operatively connected with an the latter is suitably connected for oscillations in timed relation to the rotations of the scoring roller 3. To illustrate this feature, a shaft is shown mounted at the bottom of the machine frame, and this shaft is in any suitable manner (not shown) connected for rotation at the correct predetermined speed relative to the scoring roller 3.

A cam 24 is mounted on the shaft 23 and it is engaged by the roller 25 of a bellcrank 26 which, by a spring 21, is swung yieldingly to maintain the roller 25 in contact with the cam. A link 28 interconnects this bellcrank with an arm 29 of the rock shaft 22. The cam 24 is adjusted on the shaft 23 to swing the shovel forward, away from the feed roller 6, while the envelope ascends the curved face of the shovel. Now it is noticed that a feed roller 30 is mounted to rotate on the shovel opposite a window l of the latter, and the function of this roller is to assist in carrying the bottomv edge of the envelope to the stops I and to maintain it yieldingly in contact therewith after the envelope has passed out of engagement with the feed rollers and 6.

The roller 30 is shown connected for rotation by means of a belt 3|, hung. on a pulley 35 of the rod 8. A second belt 32 interconnects this pulley with a pulley 36 of the shaft 34, on which the feed roller 5 is mounted. Because it is found necessary to adjust the speed of rotation of the roller 30 to suit the weight of paper of the envelope, it has been found advisable to introduce step pulleys 35 and 36 in the driving connection to this roller. The rock frame .9 may conveniently be hung on or concentric with the shaft 34 and it is shown pivotally mounted at 33 above this shaft merely for the sake of clearness. Whenso mounted, it is necessary that the belt ,32 be made somewhat resilient in order to retain its grip when the rock frame is swung downward into the position of Fig. 3. It has been found advisable, also,'to place a resilient finger 31 on the shovel in position to guide the envelope under the roller 30. Without such finger, there is danger that the envelope might strike the outer surface of the roller and sofail to come to stop against the projections ID.

The rock frame 9 is caused to swing downward" to reach the position shown in Fig. 3 by means of connections which will be described in detail presently, when the shovel is fully advanced, and it is seen that the top edge A of the flap comes to rest on aninclined shelf 40 of the ma-i chine frame. It is also noticed that a roller 4| is placed above this shelf in close proximity to the return roller II, and it is important to note that the latter is mounted for free rotations in the frame. But it is, at the time the shovel commences its return movement, contacted by the roller 4! and, as the latter is positively connected for clockwise rotation by the driving mechanism of the machine, it is seen that the roller l I at this time is rotated in counter-clockwise direction. A steady pull on the envelope flap by the roller H is in this way produced to aid in folding the flap back on its line of indentation.

Upon completion of its return movement, the shovel delivers the newly folded top edge of the envelope into the gap between the rollers 6 and H, substantially as indicated in Fig. 4, whereupon the roller II is swung away from the roller 4! and into contact with the roller 6, thereby to deliver the finished envelope on to the table I2. This movement of the roller Il may be effected through the medium of a second cam 42, on the shaft 23, and of bellcrank which, by a link 45, is.

operatively connected with a frame 46 in which the roller H is held rotatably mounted. The cam 42 should be adjusted on the shaft again to causethe roller H to be withdrawn fromthe roler 6 directly before the bottom fold of the envelope passes between the rollers. This is found necessary because the air which becomes trapped within the envelope as it passes between the rollers would become sufficiently compressed at the bottom fold to burst the envelope. The

momentum of the envelope finally carries it on to the delivery table l2.

The fourth and last step in the cycle of operation consists in carrying the shovel from the position indicated in Fig. 4 back into the initial position of Fig. 1. This may be accomplished by pivotally mounting a rod 50 in the machine frame and by operatively connecting an arm 5| of this rod with the rock frame 9, through the medium of a. link 52. The rod 50 is, through the medium of an arm 53, a link 54, and a bellcrank 55, connected for operation by a third cam on the shaft 23 in the same manner that the rock shaft 22 is connected therewith. This third cam is adjusted on the shaft 23 to permit the spring 56 to turn the rod 50 in clockwise direction the moment the envelope has passed beyond the lower edge of the shovel, thereby to swing the frame 9 in counter-clockwise direction sufficiently to raise the shovel into the position of Fig. 1. A second cycle of operation now commences, and when a second envelope has been entirely withdrawn from between the rollers 5 and 6 and the shovel has reached its forward position, the cam is timed to cause the rod 50 to rotate counter-clockwise and to return the rock frame 9 to its lowered position, thereby to bring the outer edge of the flap of this second envelope to the level of the shelf 40, as indicated in Fig. 3 and in the manner above fully described.

The stops I 0 are, in Figs. 1 to 4, shown rigidly secured to the shovel 1. It may, however, be found preferable to mount these stops for movement relative to the shovel, for the purpose of forcibly expelling the envelope when it approaches the position shown in Fig. 4, about to enter between the rollers 6 and II.

In order more clearly to illustrate this fea ture, a shovel 10 is, in Figs. 5 and 6, shown fitted pivotally to support a lever H, the inner end of which, by a, spring 12, normally is held elevated against a stop 10 of the shovel. A stud 13 is suitably mounted on the machine frame to engage a cam-surface N of the lever, when the shovel reaches the position shown in Fig. 5, which is slightly behind the position of the shovel in Figs. 4 and 6. When thereupon the shovel moves towards the latter position, it is seen that the cam portion H rides over the stud to throw the lever into the position indicated in Fig. 6, against a stop Hi of the shovel. The spring 12 is shown so hung that it urges the stop into this position upon passing over dead center, thereby quickly to project the envelope downward and forward as it enters between the rollers 6 and II. A second stud 14 is placed above the lever which, while the shovel rises into the position indicated in Fig. 1, contacts this stud and is by the latter swung back into the position of Fig. 5. f

When it is remembered that the rotating rollers 30 continuously urge the envelope upwardly against the stop, it is seen that it may be found very desirable to provide such. means 'for posi tively projecting the envelope far enough to make sure of full grip by and between the .rollers 8 and H.

The device of the invention, in the. form illustrated in the drawings, forms a complete :machme for folding the, fiap'of an envelope in reverse direction. In such machine, itis, of course, necessary to time the movement of the "envelope to the scoring roller 3 in order that the reverse fold may always coincide with the line 'of indentation. attaining this result, a stack of envelopes 60 is roller 61 urged against a stop 62.

Illustrative of a simple method of shown placed on the top' plate 2,'and the lowerby a continuously rotating The latter is shown suitably connected for operation by a cam 63 of a shaft 64 to sink out of the way of the bottom envelope at the proper moment. A plate 65 may be added to prevent more than one envelope to be fed forward at a time. i The cam 63 is, through the medium of a belt 65, suitably connected for rotation from the shaft of the roller 6 at the proper speed.

It may, however, be found more advantageous to embody the device of the invention in any most envelope is i one of the many commercially well known envelope folding machines because, in this manner, the reverse fold may be produced at no additional cost.

It is noticed that the links 2!, 52, and 54 are mounted for various positions of adjustment, and this is done in order to adapt the machine for use in connection with envelopes of different sizes. The scoring roller 3 is, for this reason, also shown long enough to accommodate longer envelopes, and the capacity of the machine may, of course, be further increased to take any size of envelope in commercial use.

I claim;

1. In an envelope forming machine, envelope feeding means, means movable to withdraw envelopes from said feeding means subsequently to reverse its movement and the movement of the envelopes and in so reversing to fold the top flap over the face of the envelope, and means delivering the finished envelopes from said folding means in said reverse direction.

2. In an envelope forming machine, envelope feeding means, means movable to withdraw envelopes from said feeding means subsequently to reverse its movement and the movement of the envelopes and in so reversing to fold the top flap over the face of the envelope, means for scoring the envelopes along the flap folding line before reaching said folding means, and means delivering the finished envelopes from said folding means in said reverse direction.

3. In an envelope forming machine, envelope advancing means, an envelope carrier, means delivering an envelope to said carrier, means receiving the envelope from the carrier, means for oscillating said carrier to withdraw the envelope from said delivering means, and means for shifting the position of the carrier to cause return movement of the carrier by said oscillating means to fold the flap of the envelope over the face thereof and to deliver the envelope to said receiving means. 7

4. In an envelope forming machine, envelope advancing means, an envelope carrier, means delivering an envelope to said carrier, means receiving the envelope from the carrier, means for scoring the envelope before entering said carrier, means for oscillating said carrier to withdraw the envelope from said delivering means, and means for shifting the position of the carrier to cause return movement of the carrier by said oscillating means to fold the flap of the envelope over the face thereof along the line of scoring and to deliver the envelope to said receiving means.

5. In an envelope forming machine, an oscillatory carrier, means feeding an envelope to said carrier, means delivering the envelope from the carrier, means moving said carrier to withdraw the envelope from said feeding means and to deliver it to said delivering means, and means on said carrier yieldingly retaining the envelope on the-carrier.

'6. In an envelope forming machine, an oscillatory carrier, stop means on said carrier, means feeding an envelope along said carrier until arrested by said stop means, means delivering the envelope from the carrier, means moving said carrier to withdraw the envelope from said feeding means and to deliver it to said deliverin means, and means on said carrier yieldingly retaining the. envelope on the carrier.

7. In an envelope forming machine, an oscillatory carrier, a stop on the carrier, means, on the carrier urging the envelope against said stop, envelope delivery means, and means moving the carrier to withdraw the envelope from said feeding means and to. return it into position of regisnation with said delivery means.

8. In an envelope forming machine, a pivotally hung carrier, movable. stop means on the carrier, means feeding an envelope to said carrier until arrested by said step means, means swinging said carrier to withdraw the envelope from said feeding means, and means for moving said stop means to eject the envelope from the carrier.

9. In an envelope forming machine, a pivotally hung carrier, movable stop means on the carrier, means feeding an envelope to said carrier until arrested by said stop means, means urging the envelope against said stop means, means swinging said carrier to withdraw the envelope from said feeding means, and means for moving said step means to eject the envelope from the carrier againstthe resistance of said urging means.

10. In an envelope forming machine, envelope feeding means, envelope delivery means, flap folding means including a rock frame, a carrier pivotally hung in said frame to receive envelopes from said feeding means, envelope stop means on said carrier, means for swinging said carrier on its pivot to withdraw envelopes from said feeding means and to deliver them to said delivery means with their flap folded, and means for shifting the position of said rock frame properly to align the envelopes with said delivery means.

11. In an envelope forming machine, envelope feeding means including means for holding a stack of envelopes and means for advancing envelopes along the machine in timed succession, delivery means for finished envelopes, pivotally hung means in the path of the advancing envelopes and movable first to withdraw envelopes from said feeding means, means on said pivotally hung means for yieldingly holding the envelopes thereon, said pivoted means being movable in the opposite direction to deliver them to said delivery means, and means shifting the position of said pivoted means during its second movement to fold the flap over the face of the envelope and to bring the latter into registration with said delivery means.

12. In an envelope forming machine, envelope feeding means including means for holding a stack of envelopes and means for advancing envelopes along the machine in timed succession, delivery means for finished envelopes, pivotally hung means movable first to withdraw envelopes from said feeding means, and second to deliver them to said delivery means, means shifting the position of said pivoted means during its second movement to fold the flap over the face of the envelope and to bring the latter into registration with said deliverymeans, and means for projecting the envelopes into said delivery means.

13. In an envelope forming machine, envelope feeding means including means for holding a stack of envelopes and :means for advancing envelopes along the machine in timed succession, delivery means for finished envelopes, pivotally hung means movable first to withdraw envelopes from said feeding means, and second to. deliver them to said delivery means, means yieldingly maintaining the withdrawn envelopes on said pivoted means, means shifting the position of said pivoted means during its second movement to fold the flap over the face of the envelope and to bring the latter into registration with said delivery means, and means for projecting the finished envelopes into said delivery means against the resistance of said yielding maintaining means.

14. In an envelope forming machine, means for folding the envelope flap over the face of the envelope comprising, a carrier,'means for feeding an envelope to said carrier, delivery means, means foroscillating said carrier to withdraw the envelope from said feeding means and to return it to said delivery means, and means for folding the flap of the envelope during the return movement of the carrier.

15. In an envelope forming machine including means for continuously feeding blanks through the machine and for folding and combining the bottom and end flaps duringv the advance movement of the blanks, a carrier for receiving the envelopes from said feeding means, delivery means, and means for oscillating said carrier to withdraw the envelopes from the feeding means and for transferring them to said delivery means, during said transfer to fold the top flap over the face of the envelopes. r

16. In an envelope forming machine including means for continuously feeding blanks through the machine and for folding and combining the bottom and end flaps during the advance movement of the blanks, a carrier for receiving the envelopes from said feeding means, delivery means, means for oscillating said carrier to withdraw envelopes from said feeding means, and means for shifting the position of the carrier to cause return movement thereof by said oscillating means to fold the top flap over the face of the envelopes and to transfer the envelopes to said delivery means.

17. In an envelope forming machine including means for continuously feeding blanks through the machine and for folding and combining the bottom and end flaps during the advance movement of the blanks, a carrier for receiving the envelopes from said feeding means, means for scoring the envelopes before entering said carrier, delivery means, and means for oscillating said carrier to withdraw the envelopes from the feeding means and transferring them to said delivery means, during said transfer to fold the top flap along the line of scoring over the face of the envelopes.

18. In an envelope forming machine, a carrier, means feeding envelopes to said carrier in timed succession, means for delivering the envelopes from said carrier, means for oscillating the carrier to withdraw each envelope received thereby from said feeding means and to return it to said delivery means, during said return oscillating movement of the carrier and after the envelope entirely is withdrawn from the feeding means to fold the top flap over the face of the envelope, and means for moving the carrier before said return movement thereof to aline it with said delivery means.

. DONALD E. STEVENSON. 

